Art of preserving fresh fruit juices in their natural state



Nov. 13, 1934. l', H, PoLK ARTioF PREsERvING FRESH FRUITJUICES 1N THEIRNATURAL. STATE Filed Nov.I 25. 1932 INVENTOR isaa'aH Palin EYS ATTORNNov. 13, 1934. l l, H FOLK 1,980,695

ART OF PHESERVING FRESH FRUI-T JUICES vIN THEIR NATURAL STATE FiledNov'. '25, 1952 2 sheets-sheet 2v Mimi HHHHH 37 y ATTORNEYS laisseraitlNev'. 13, i934 PATENT OFFICE lART F PBEISEBVING FRESH FRUIT JUICES INTHEIR NATURAL STATE Isaac H. Polk', Monrovia, Calif., assigner, by mesneassignments, to Sunset Packing Corporation, Los Angeles, California 1Calif., a corporation Aof Application November 25,1932, Serial No.644,360

22 Claims.

This invention relates to art of preserving fresh fruit juices in theirnatural state, and in particular it relates to extraction and treatmentof orange juice and the like in such manner as 5 to yield ajuice'product of good flavor and keeping qualities which hassubstantially the characteristics of fresh orange juice or whihapproaches that objective more closely thanhas been possible heretoforein the art. 'fw

While the invention is not to be understood as confined in its practicalapplication to. the preservation of the juice of oranges'or other citrusl fruit, the preservation of orangejuiceis at presentv the mostimportant commercial field for the Q practice of the invention, andtherefore this will be more particularly referred to hereinafter by wayof concrete example embodying the underlying principles of theinvention. It is to be borne in mind, however, that in its broader as-20 pects the invention is applicable to the preserva.

tion of the juices of various other fruits in fresh, natural condition.

It is well known that numerousattempts have heretofore been lmade topack fresh-fruit juices,

such as orange and other citrus juices, in such manner that they willkeep for a substantial period of time and also retain the goodpalatability, fine flavor vand other desirable charac'- teristicspossessed by the fresh juice immediately after its extraction from thefruit. Among these prior attempts may be mentioned pasteurization,treatment with light rays, extraction and packing in the presence ofinert gases, and slow and quick freezing methods with and withoutagitation.

None of these proposed prior methods has made possible the commercialpreparation of a juice product, in either liquid or frozen condition,that can be held for anysubstantiallength of time and that retains thefreshness and palatability 40 characterizing `freshly extracted juice.'I l'he quick-freezing methods have been found t'o be the mostsatisfactory from the standpoint of preserving the fresh taste. of thejuice; but in spite of prolonged and very expensive research and i5experimental workA in an effort to render juice preservation by thesemethods commercially feasible, it has proved impossible until nowtoachieve the desired result even by quick-freezing methods.

Apparently the lack of success characterizing prior attempts to producta satisfactory vfresh juice product of the type here under considerationhas been due in largemeasure to the failure to provide a thoroughly.systematic and methodi- V cal procedure by which the juice can beextracted and subjected to the necessary treatment in a minimum periodof time and under operating conditions such that, at each step or stageof the procedure, a suitably low temperature is maintained and thechances-of introducing air into the juice and thus causing oxidation areminimized. The present invention includesl a procedure wherein theserequirements are satisfactorily met, the several steps or stages being,grouped together into a combination which is novel in the art andeffective to yield a fresh juice product of markedly superiorcharacteristics, this result being attained with an eiliciency andeconomy such that the novel combined procedure is commercially feasible.

Another difficulty which has heretofore proved insuperable has been thepractical impossibility of preventing contamination of the juice byessential oilsand other constituents derived from the rind or peelwithout excessive removal or loss of pulp, and of removing suchcontaminants from the juice with sumcient completeness to avoid thedamaging effect upon flavor and keeping quality they produce through theoxidation or other chemical change which they inevitably undergo. Nopractical way of avoiding this dimfculty has been known to theartheretofore. The' present invention, however,- makes possible the re.-Vmoval of substantially all of the troublesome oily constituents andother important contaminants in a relatively simple and dependablemanner, with the result that impairment of or deterioratiton in thejuice flavor from this source is wholly or largely eliminated. Thiseliminates the chief obstacle heretofore blocking attempts to preserveorange juice and the like in fresh, natural state.

In brief general outline, the complete process of the present inventioncomprises, first, the step of extracting the juice from the fruit, mostldesirably after the fruit has been precooled to a temperatureapproximately the freezing point but not suiliciently low, under theconditions of operation, to effect actual freezing of the fruit. Thejuice is then strained to remove whatever 100 relativelyv coarse pulp orother solids or semisolids are contained therein, and may be allowed tostand for a short time to enable removal of such excess oils, pulp, andresins, as can be rapid-'- ly separated in a preliminary way by settlingand 105 skimming. This and the succeeding steps are also conducted at-relatively lovvtemperatures and.` lmder conditions such thatintroduction of air into the juice is minimized. After the prelimnaryseparating step just mentioned, the juice no ssj is subjected, still atlow temperature, to the action of a relatively high vacuum which shouldbe on the order of at least 2'7 inches mercury vacuum gauge (3 inchesmercury absolute pressure), and most desirably 28 inches or higher. Inthis step, the juice is agitated by one means or another but only to alimited extent, Athe purpose being merely to agitate sufficiently toensure adequate exposure of all portions of the body of juice undergoingtreatment to the applied high vacuum (low absolute pressure), whereby toeffect as nearly complete de-aeration as is practically possible underthe relatively low temperature and other operating conditions hereinvolved. This application of high vacuum to the juice is notv merelyfor the purpose of eliminating the contained air and its oxidizingeffect but, as will appear presently, it also enables more completeelimination of oily and other contaminating impurities in the nextsucceeding stage of the process. After applying the high vacuum to thejuice while it is being agitated `for-the limited period of timeindicated, the juice is allowed to standA n contaminants, p articularlyoily and resinous matter, which still persist in the juice to someexter-'.- t notwithstanding theprevious preliminary settling andskimming operation already described as being most desirably effected ina preceding stage. This supernatant layer of solid and semi-solid pulpy'or like material, or rather the upper portion of said layer,- togetherwith the accompanying contaminants which have thus been caught orentrained and virtually filtered out of the juice by the rst portionespecially of the solid particles of pulp etc. rising through the bodyof juice, is then rejected by decantation or otherwise, leaving ade-aerated and puried juice which is of greatly enhanced stability. Itis also characterized by a ratio of solids to liquid which, in thepractice of the process, is found to be quite definitely predeterminableand capable of being maintained substantially constant, a highlyimportant advantage incapable of realizationv heretofore in practicalwork.

The juice is then placed in consumer-unit containers which are sealedunder vacuum. Where the final product is to bein frozen form, the sealedcontainers are refrigerated in such manner as to effect freezing oftheir contents as quickly as possible under conditions minimizingphysical separation of the dissolved and suspended solid constituents ofthe juice from the associated Water content. After the freezingoperation, the containers can be stored at subfreezing temperature untilthe juice is required for use, whereupon'the frozen juice can beliquefied in any suitable manner. Y.

"I'he complete combination of process steps generally outlined aboveisbelieved to be novel in the art.4 Also certain of the steps so combined,which will be more fully hereinafter described, are believed to beindividually novel.

Inbrder ltb afford a fuller undertanding of fresh natural condition willnow be described inl detail by way of a typical concrete example.' Whilethe process maybe carried out in various forms ofapparatusdifferingwidelyi n specific detail, the description hereinaftergiven will include reference to an apparatus system'which has been foundto possess particularly desirable characteristics for the purposes inview and which i also embodies novel features of importance. Such anapparatus system is illustrated more or less diagrammatically drawingswherein Figs. 1 and 1a, placed end to end 'on the line ly broken awayand in section;

Fig. 2 is a plan of the extraction unit; and

Fig. 3 is a vertical central section, on a larger i scale, of the vacuumseparator unit.

Referring to the drawings, A represents generally a precooling unitwherein the oranges', prior to extraction of the juice, are cooled downto approximately the freezing point; while B represeparating andde-aerating unit, D the container lling and sealing unit, and E thequick-freezing unit.

Since the entireseries of operations comprising the complete process arecarried out at temperatures either in the neighborhood of the freezingpoint or, in the case of the final freezing, much below the freezingpoint, the several units above mentioned are enclosed in rooms orchambers.

in the accompanying 'a.-`a, represent the system in side elevation,partsents generally the -juice extraction unit, C the' protected bysuitable heat insulating material indicated generally at 10. The desiredlow temperany well known or suitable type unnecessary'to illustratehere.

The oranges to be handled in the plantare held in the precooler unit A,as in stacked boxes 11, until the fruit has been cooled Ato about 29 to33 F., the optimum being about 30 F." No substantial freezing of theedible lportion of the fruit will occur under these conditions evenfifthe fruit .remains in the precooler vfor several/hours after attainingthe stated temperature. This precooling of the fruit to withinsubstantially the temperature range just mentioned ishighlyiadvantageous in its effect upon the keeping quality and othercharacteristics of the juice product finally obtained. Precooling thefruit before extracting the juice therefrom also favorably affects thesubsequent vacuum separation `of pulpy and fibrous matter carryingundesirable contaminants, already referred to, and indeed seems to beessential to the attainment of best results ln effecting said-vacuumseparation. It is therefore an important specific feature of theinvntion in its best embodiments,'although in itsy broader aspects theinvention is not restricted to a combination of steps which necessarilyincludes precooling or, if precooling be employed into the juice-fromthe rindor peel and k, of any suitable type l size of the mesh as welllto do so, these materials being removed in vany convenient byskimming.Oneof the fruit to within this temperature range would result in suchsuperiority in the final product.

A'fter the fruit has been precooled to the desired precoolingtemperature, it is transferred from the precooling unit by way of boxdump 12 and conveyor means 13 to the extraction unit B. It is deliveredby the conveyor 13 to V-shaped trough 14 down which it rolls by gravityand by which it is presented to revolving knife 15, which halves thefruit, the halves being deflected by stationary deflecting ordistributing device 16 to parallel conveyor belts 1'7. From theseconveyor belts, operators take the halved fruit and subject it to theaction of reaming machines 18 for extraction of the juice, the reamedfruit rinds being thrown into waste receivers 19. Any other suitablemethod may of course be used for extracting the juice, reaming beingreferred to here merely as illustrating one practical way ofaccomplishing the desired result. The installation here illustratedcomprises a battery of ten reamers in two groups of five, each groupbeing served by one of the belts 17. The reaming member of each machineis most desirably a cone-shaped rotating burr constructed in such manneras to reduce to a yminimum the tearing effect upon fruit tissues, itbeing desirable to prevent as much as possible the introduction of oilsand/or resins uragn. The reaming operation should be conducted in anenvironment cooled to 40 F. or lower in order to maintain thetemperature of the juice as near the freezing point as is feasible. l

Juice from each set or group of reamers passes A into pipe 20 and flowsby gravity into a strainer 21 where the seeds and relatively very coarsefragments of pulp and other solid material are separated from the juice.This strainer may be but` most desirably it comprises screens of suchsize mesh and so agitated, vibrated or revolved as to allow passagetherethrough of the juice, together with all the very fine pulp and adesirable proportion of moderately coarse pulp, while retaining andautomatically moving to a place of discharge the seeds,

very coarse pulp, etc. desirable to reject at this stage. The relativevolumes of liquid, and solids and semi-solids, respectively, passingthrough the screen device can be definitely controlled-by the as by theextent and rapidity of screen vibration, agitation or revolution. Oneimportant advantage of this type of strainer lies in thefact that by itsuse adequate separation therefrom ofK relatively very coarse solidmaterial can be eiected while subjecting the juice to only theminimum ofagitation and consequent aeration.

From the strainer unit 21, the separated juice flows through pipe 22into the bottom of an an- -nular fore-cooler chamber 23 which should besuitably refrigerated to keep the juice at a temperature approximatingthe freezing point. In this instance the fore-cooler is'shown asprovided with central and peripheral spaces 24 and 25, respectively, forcirculation of a refrigerant. The pipe 22 is shown discharging into theforecooler chamber' at a point below the normal liquid level therein.This arrangement, and maintaining the pipe 22 full of juice at alltimes, are desirable measures of general application for minimizingintroduction of air into the juice.

In Vthe pre-cooler, the juice is allowed to stand a suflicient length oftime to permit such portion of the light oils, gums or resins and pulpas will rise to the surface readilyunder these conditions functions of.thisfore-cooler is to permit accumulation at this point of a substantialbody of juice and thus to provide a source of supply from which asubstantially constant-volume now of juice into 7 the next succeedingstage of the process can be smoothly and continuously effected,irrespective of more or less variation in the rate at which juice flowsvinto the fore-cooler from the extra'ction unit B.

From the forewooler, the 'partially purified juice passes to thede-aeratingf'unit. The de aeration must be accomplishedin fa thoroughand systematic mannerbut with. a minimum amount of agitationotthejuio'e.f Excessive agitation,

besides producing other undesirable results, promotes oxidizingreactionsof various Akinds and injuriously affects the `iiavor and keepingqualities of the juice. As already stated, the purpose of thisde-aeration .step is not merely to remove air from the juice. Whencarried out in accordance with the invention,r this operation has thefurther purpose and eiect of causing a substantial quantity of pulp,mostly of moderate or of intermediate coarseness, to ascend through thebody of juice and to exert upon the entire body of juice a Amechanicalcleansing or fllteringaction, whereby even very small residualquantities of oily, resinous and other objectionable contaminants,practically impossible to remove by methods heretofore known, can besubstantially eliminated in a simple and rapid manner. One of the chiefreasons for the failures heretofore to obtain a natural orange juiceproduct of good fiavorand good keeping qualities has been theacknowledged inability to remove these last traces of oils, gums. etc.which undergo .oxidation or other chemical change during the storage ofthe juice, thus inevitably causing its serious deterioration.

In effecting de-aeration in accordance with the present process, thejuice, after settling and being skimmed, passes from the fore-cooler andsettling container 23, through pipe 26, into a vacuum separator device27 which is desirably of upright cylindrical form and provided withcooling jacket 28, whereby a body of juice of considerable depth may bemaintained under high vacuum at a temperature approximating v thefreezing point. Means (not shown) are provided for maintaining in thisvacuum separator a partial vacuum of at least 27 inches mercury vacuumgauge (3 inches absolute pressure), and most desirably of 28 inchesvacuum gauge or higher. By virtue .of the low pressure maintained in thevacuum separator, the juice to be de-aerated may be continuously drawninto the separator from container 23 through the afore-v said pipe 26 ata predetermined rate which can be adjusted as desired by desirably therate of ow of'juice into the sep- `arator is so regulated that the juiceenters the agitation of the juice during the de-aerationlm control valve29. Most or three minutes being usually sufficient.

ldisseminating throughout the juicethe small residual quantity of oils,gums, etc., and the'virtual emulsication thereof with the -juice thatnecessarily accompanies the violent agitation heretofore characterizingde-aerating treatments.

After the desired amount of juice has been charged into the vacuumseparator 'chamber through pipe 26, the inlet valve 29 is closed and thejuice is slowly agitated by means of device 30 for a short time, aperiod on the order of two This is primarily for the purpose ofdislodging pulp particles adhering to the side walls and bottom of theseparator chamber. The body of juice in the vacuum pan is then allowedto stand quietly for a substantially longer but limited period of timeunder the applied high vacuum. In a typical instance, this standingperiod may be on the order of l5 minutes. It is found that under theseconditions a considerable amount of fairly coarse pulp and othersuspended solid or semi-solid matter which, although carrying relativelylarge quantities of adsorbed air, would normally tend to sink to thebottom of the juice body, is caused by the action of the applied highvacuum to rise upwardly through the relatively deep body of juice and toaccumulate in a layer at the upper surface thereof. Apparently theapplication of the high vacuum reduces the totall effective pressure onthe highly condensed adsorbed air carried by said solid or semi-solidmatter, especially by the coarser particles thereof, permitting someexpansion of such adsorbed air, with consequent Ibuoyant effect uponthe' particles sufcient to overcome their normal tendency to sink, andto cause the described upward movement thereof through the quiescentcolumn of juice. But whatever may be the correct explanation, suchmovement of the aforesaidl particles does occur under the operatingconditions here prescribed. Moreover, in its travel upwardly through thejuice, this solid or semi-solid matter, more especially that whichascends during the earlier part of the-standing period, collects andcarries with it practically allV of the residual oils, resins, gums andother troublesome contaminants which still persist in the juice andlhave heretofore defied even approximately complete removal. After .thelayer of pulpy material has accumulated at the upper surface of thejuice column as described, the juice column should not be allowed tostand too long under the applied high vacuum before removing the upper.part of said layer. .Otherwise de-aeration of that portion of the solidor semisolid matter carrying undesirable contaminants may proceed to thepoint where the particles composing such matter lose their buoyancy andsink downwardly, thus defeating to agreater'orless extent the principalpurpose of this vacuuml separation treatment. At the conclusion of theperiod of standing or quiescence the layer of solids and semi-solidswhich has accumulated in the upper part of the juice column amounts in atypical instance -to around twenty to twentyve per cent of the totalcolumn heightv or depth. Since the aforesaid contaminants are found tobe concentrated almost entirely in the upper portion of this layer, onlysuch upper portion need be removed and discarded in any suitable mannerin order to ensure substantial freedom of the remainder of the juicecolumn from such contaminants. In practice, not more than the upperyhereinafter specifically described has important practical advantages.Also, the practice of this method is facilitated and simplified by thecon-, l

struction and arrangement of the novel vacuum de-aerating and separatorunit here illustrated.

Within the shell of the vacuum separator is a juice container orreceiver comprising a xed lower portion 32, and a double-walled upperportion 33 which is in telescoping relation with the lower portion andcan be moved upwardly or downwardly by means of a suitable rack andpinion device 34, for example, to vary the capacity of the juiceyreceiver or container as a whole. At the start of the de-aerating andseparating operation, the capacity of the receiver is adjusted toaccommodate theentire volume or body of juice to be de-aerated at thetime, the position of the parts being as shown in Fig. 3. The receiveris of slightly smaller diameter than the shell of the vacuum separatorchamber 27, thus leaving an annular clearance between the shell and thereceiver to provide an -overflow space, as indicated at 35. The juiceinlet pipe 26 is arranged to discharge into thereceiver at a point justabove the open top thereof when in its extended or full volume position.

Air having been previously exhausted from the vacuum separator ascompletely as possible, and juice sucked through pipe 26 from container23 having been sprayed or sprinkled into the receiver until thelatter ischarged full, as already described, valve 29 is closed and, while thecolumn of juice in the receiver is quiescent, the

application of the high vacuum (e. g. 28 inches gauge or higher)continues until the desired action of the vacuum upon the juice issubstantially complete and the before described layer of solid andsemi-solid matter, with accompanying oily and other contaminants, hascollected at the top. Thereupon, the upper portion 33 of the receiver islowered by means of adjusting device- 34 to the extent necessary topermit the predetermined upper portion of the accumulated semiliquidsupernatant mass or layer to overflow the upper edge of the juicereceiver into the annular overflow chamber 35. This decantation havingbeen effected, the juice remaining in the container 32-33, still underthe applied high vacuum, is vnow agitated suiiiciently to distributetherethrough the pulp constituting the residual lower portion of thelayer originally accumulated. This residual pulp is a desirableconstituent of the finished juice product and uniform distributionthereof through the juice at this stage, prior to the succeedingpackaging operations, should be effected. This agitation of me purifiedjuice following the described separation and rejection of that portionof the pulpy layer carrying the oily and resinous contaminants andwhilethe juice is still under high vacuum, accomplishes even more nearlycomplete de-aeration of the juice and the residual relatively ne pulpparticles left therein. This is desirable not only in and of itself butalso because the buoyancy of said residual pulp particles is therebyreduced and uniformity of the distribution and suspension thereofthroughout the juice is thus favored. After breaking the vacuum bycautiously opening valve 2'7, the overowed or decanted material may besubsequently vwithdrawn from chamber 35 through outlet pipe 36 byopening cut-off valve 37. The purified juice can be removed throughoutlet pipe- 38 by opening cut-off valve 39. These cut-off valvesnormally remain closed at all other times.

Not only does the described vacuum separation eliminate oily and likecontaminants to a degree of completeness impossible of attainmentheretofore, but it also results in a more nearly perfect de-aeration' ofthe juice. air from juice is extremely difficult, especially at therelatively low temperatures at which it must be handled in a process ofthis kind. A large` part of the air content of extracted juice istenaciously held in adsorbed condition by the coarser fragments andparticles of pulp and otherrsolids or semi-solids. Preliminary strainingof the extracted juice removes some of the coarsest fragments; but thepractical limitation of any straining method, and the furtherconsideration that complete removal of pulp and the like is undesirablein any ease, render it inevitable that in the strained juice there isstill a substantial contentv of fairly coarse pulp carrying muchadsorbed air. Application of high vacuum to strained juice whileviolently agitating it is insuflicient because, aside from variousobjections to such agitation, it is ineffective to dislodge anythinglike all the adsorbed air which is chiefly held by such fairly coarseresidual pulp. But in the present process, wherein a body of thestrained juice of substantial depth is held quiescent under high vacuum,such coarser residual pulp fragments or particles have an opportunity tocollect in the aforesaid supernatant layer of solids and semi-solids ator near the top of the juice column. Moreover, due apparently to thegreater buoyant effect produced upon them by the applied vacuum, becauseof their larger content of adsorbed air as compared to relatively finepulp particles, the coarser pulp particles are found mainly in the upperhalf of said supernatant layer and are thus removed and discarded, withtheir persisting air content, in'the decantation step.

It will be noted also that, through the present process, it becomes acomparatively simple matter to adjust and control, with a high degree ofexactness, the quantity and proportion of pulp-to be left incorporatedin the finished juice. Maintenance of a predeterminable or standardratio of solids to liquid is a most important consideration in themarketing of orange juice, and inability to` attain such uniformity ofproduct has been one of numerous reasons why prior proposed methods havebeen unsatisfactory.y

After the vacuum in the vacuum separator has f been slowly released orbroken in such manner as to avoid introducing air into the purifiedjuice, valve 39 is opened and the juice is allowed to flow through pipe38 to a filling machine 40 of any well known or suitable typewherebyconsumer packages or containers, such as glass bottles or properlyenameled cans, may be filled in such manner as to exclude introductionof air into the juice. This is best accomplished by filling thecontainers from the bottom. It is to be "understood that this operationis also conducted under appropriate refrigerating conditions. The filledcontainers then go to capping, closing and sealing machines of any wellknown crsuitable type, indicated at 41,42 and 43, respectively, thesealing being effected under the highest degree of vacuum practicallyattainable in the operation of Complete removal of such machines withthe particular type of unit container employed.

Prior to lling the containers as just described, the containers are mostdesirably pre-cooled to thetemperature of the juice, that is, toapproximately the freezing point. This pre-cooling of the f containersis of material importance for attainment of best results and is ahighlydesirable feature of the new process in its most advantageous 'practicalembodiments.

Where, as is deemed most desirable, the juice is to be frozen into solidform, the sealed containers are then delivered by conveyor 44 to aquick-freezing unit, which in the present instance comprises anenclosedand suitably insulated tank 45 containing a freezing bath 46 of suitableliquid, such as alcohol, maintained at, say, 50 degrees below zeroFahrenheit (-50" F.) The temperature of this freezing bath may behigheror lower than 50 F. depending upon such practical considerations as sizeof the containers, the material of which they are made, and the like.But in any case thetemperature should be low enough to Aor;

bring about quick-freezing of the juice as this term is understood inthe art.`

The containers 47 roll by gravity down an inclined track 48, arranged todirect them through the freezing bath which may be maintained incirculation by a suitable propeller device 49 and kept at the desiredlow temperature by appropriate refrigerating means not shown andunnecessary to describe in detail. The length of the bath is such thatby the time the containers ,have

, perature substantially below its normal freezing point while it stillremains liquid, to such an extent that a flash-freeze occurs, thusobtaining the benefits of the quick-freezing principle, includingreduction ofthe aforesaid physical separation to a minimum, and maximumretention of volatile substances.

The track 48 delivers the containers, at a point below the level of thefreezing bath, to an elevator device 50, which lifts them out of thebath and delivers them to conveyor belt 51, from which they may be takenby operators to-be suitably packed for storage under refrigeration, mostdesirably at 0 to 10 F. When the juice is required for use, the unopenedcontainer may be placed in cold water or other environment, preferablyat about 35 to 40 F., until the ,contents liquefy, the juice thusremaining under vacuum and protected against oxidizing influencesthroughout the ,I

the invention, and thatany. specific figures mentioned aremerelyillustrative of good practice in typical instances. l

- What is claimed is:

1. Inthe art of preserving fruit juices in natural state, the processwhich comprises subjecting a body of freshly extracted fruit juicecontaining pulp particles, together with oily and other con,- taminants,to the action of a partial vacuum until a substantial quantity of thepulp has been caused to pass upwardly through said body of juice andform'a supernatant layer containing such contaminants, removing at leastthe upper partof said layer, and packaging the residual juice.

2. The process defined in claim l which further includes conducting allthe stated operations under refrigeration.

3. In the art of preserving fruit juices in natural state, the processwhich comprises subjecting a body of freshly extracted fruitl juicecontaining pulp particles, together with oily and other contaminants, tothe action of a partial vacuum until a substantialquantity of the pulphas been caused to pass upwardly'through said'body of juice and forma'lsupernatant layer containing such contaminants, removing apredetermined upper portion of said layer, distributing the residualportion of said layer uniformly throughout the remaining body of juice,and packaging the juice.

4. The process defined in claim 3, which further includes conducting allthe stated operations under refrigeration.

5. In the art of preserving fruit juices in natural state, the processwhich comprises cooling fresh fruit down to a temperature approximatingthe freezing point, extracting juice therefrom, agitating the extractedjuice moderately while subjecting it to a partial vacuum of at least 27inches mercury gauge, then further subjecting the juice in a quiescentstate to such` partial vacuum until a substantial quantity V,of pulp haspassed upwardly through the body of juice and collected at the surfaceas a layer containing impurities, rejecting at least the upper part ofsaid layer, filling the residual juice into containers, and sealingunder vacuum, all the foregoing operations being effected attemperatures not exceeding 40 F.

6. The process dened in claim 5, which further includes quick-freezingthe juice after it has been placed in the vacuum-sealed containers.

'7. In the art of preserving orange juice in its natural state, theprocess which comprises removing juice from fresh Oranges, preliminarilyseparating from the juice relatively coarse solid matter and associatedcontaminants -of an oily and/or resinous nature, subjecting theseparated juice to the action of a partial vacuum of such degree and forsuchvlength of time that solid matter therein is caused to risetherethrough and collect at the surface in a layer containing residualcontaminants of the character aforesaid, separating at least the upperpart of said layer from the juice and packaging the latter, all theforegoing operations being conducted under refrigeration.

8. In the art yof preserving orange juice in its natural state, theprocess which comprises extracting juice from fresh oranges,preliminarily separating from the extracted juice lrelatively coarsesolid matter and associated contaminants of an oily and/or resinousnature, subjecting the separated juice to the action of` a partialvacuum of atleast 2'1 inches vacuum gauge under conditions of agitationensuring adequate exposure of all portions of the juice to thede-aerating action of the vacuum, then further subjecting the juice tothe action of such partial vacuum without agitation until a substantialquantity of the pulp has been caused to pass upwardly through said bodyof juice and form a surface layer containing residual contaminants ofthe character aforesaid, separating at least the upper part of saidlayer from the juice and'packaging the latter, all the foregoingoperations' being conducted under cooling conditions.

9.- In the art of preserving fruit juice in its natural state, theprocess which comprises precooling fresh fruit to below 33 F., mostdesirably to about 30 F., while avoiding actually freezing the fruit,extracting juice from the precooled fruit, screening the extracted juiceto remove therefrom relatively coarse solid matter, subjecting thescreened juice tothe action of an applied high vacuum, flrst while thejuice is in motion and then while it is quiescent in-a body ofsubstantial depth, until a substantial quantity of the remaining pulphas been caused to pass upwardly through the quiescent body of juice andcollect, together with contaminants such as oily and/or resinous matter,in a layer at the surface, removing at least the upper part of suchcollected layer, all the foregoing operations being conducted underrefrigeration, and then quick-freezing the residual juice.

10. The process defined in claim 9, which further includes, prior toapplication of high vacuum to the screened juice, effecting apreliminary separation of a part of the oily and/or resinous matter by astanding and skimming treatment.

11. The process deflned in claim 9, wherein,

after removal of at least the upper part of said collected layer, thejuice is filled into containers pre-cooled to a temperature atleast aslow as approximately that of the juice, the containers are sealed undervacuum, and the juice then undergoes quick-freezing.

12. The process defined in claim 9, wherein, after removal of at leastthe upper part ofsaid collected layer, the juice is lled into roundcontainers and sealed under vacuum, and said containers are caused toroll while being subjected t0 refrigerating conditions eective toaccomplish quick-freezing.

13. In the art of preserving fruit juices in natural state, the processwhich comprises cooling fresh fruit down to a temperature approximatingthe freezing point; extracting juice there-` from, agitating theextracted juice moderately while subjecting it to a partial vacuum of atleast 27 inches mercury gauge, then further subjecting the juice in aquiescent state to such partial vacuum until a substantial quantity ofpulp has passed upwardly through the body of juice and collected at thesurface as a layer containing impurities, rejecting at least the upperpart of said layer, and packaging the residual juice, all the foregoingoperations being performed at temperatures not substantially exceed1ng4014. Thel process defined inclaim i wherein, after .the stated separationof at least the upper part of said surface layer and before packagingthe residual juice, said juice is agitated while still under partialvacuum until pulpy matter remaining therein is uniformly distributedtherethrough. l

15. In theA art of preserving citrus fruit juice in its natural state,the process which comprises precooling citrus fruit to relatively lowtemperature while avoiding substantial freezing thereof, extractingjuice from the precooled-fruit, subjecting the extracted juice to theaction of a Vacuum until a layer of pulpy material has collected at thetop, and rejecting at least the upper portion of said layer fromthejuice, the extraction of the juice and the succeeding stated operationsbeing also performed at relatively low temperature.

16. I n a process of preserving fruit juice in its natural state,separating contaminants from freshly extracted juice by the steps ofsubjecting a pulp-containing body of the juice, while it is maintainedat relatively low temperature but above freezing, to the action of apartial vacuum until a considerable quantity of pulp has iioatedupwardly through the juice and formed a layer at the surface thereof,and then rejecting the upper portion of said layer;

17. In the art of preserving fruit juices in natural state, the processwhich comprises subjecting a body of freshly extracted fruit juicecontaining pulp particles, together with oily and other contaminants, tothe action of a partial vacuum while in a relatively quiescent stateuntil a substantial quantity of the pulp has been caused to passupwardly through said body of juice and form a supernatant layercontaining such contaminants removing at least the upper part of saidlayer, then agitating the residual juice while still subjecting it tothe action of the partial vacuum until pulpy matter remaining thereinhas been uniformly distributed therethrough, and packaging the juice.

18. The process defined in claim 17 wherein all the stated operationsare performed at rela.- tively low temperature.

19. In the art of preserving fruit juices in natural state, the processwhich comprises subjecting a body of freshly extracted fruit juicecontaining pulp particles, together with oily andlother contaminants, tothe action of a relatively high vacuum for a limited period of time,without substantial agitation, until pulpy matter has accumulated at thesurface of said body of juice in a layer carrying such contaminants,removing the upper part of said layer, then agitating the residual juicewhile still under relatively high vacuum, and packaging the juice.

20. The process defined in claim 19, wherein al1 the stated operationsare performed at relatively low temperature.

' 21.,The process defined in claim 19, wherein said limited period oftime is on the order of 15 minutes and the vacuum employed is at least27 inches gauge.

22. The process defined in claim 19 wherein said limited period of timeis on the order of 15 minutes, the vacuum employed is at least 27 inchesgauge, and all the stated operations are performed at relatively lowtemperature.4

ISAAC POLK.

